The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingTransmission fluid temperature sensor "A" performance
Description
Refer to dtc p0710 (see page ax-46).
Monitor description
This dtc indicates that there is a problem with output from the atf
temperature sensor and that the
sensor itself is defective. The atf temperature sensor converts the atf
temperature to an electrical
resistance v ...
Installation
Install fan and generator v belt
Using sst and 19 mm socket wrench, loosen the vribbed
belt tensioner arm clockwise, then install the
fan and generator v belt.
Sst 09216-42010
Notice:
Be sure to connect sst and the tools so that
they are in line during use.
When retracti ...
Brake switch "B" circuit high
Description
The purpose of this circuit is to prevent the engine from stalling while
driving in the lock-up condition when
the brakes are suddenly applied.
When the brake pedal is depressed, this switch sends a signal to the ecm. Then
the ecm cancels the
operation of the lock-up clutch ...